A conventional tool shaft for a cutting machine is designed to be engaged with various types of tools or knifes so as to process projects. These tools or knifes are caught by a catching means which catches one of the knifes from a tools frame and shifts the tool it catches to approach the tool shaft so as to add the knife to the tool shaft or to remove a knife already engaged with the tool shaft therefrom. However, the conventional tool shaft is typically actuated by a cylinder so that once the cylinder is actuated, a speed of the cylinder will suddenly increase to a certain value so as to rapidly move the tool shaft. Therefore, when the cylinder is stopped, the movement speed of the tool shaft will be reduced to zero from the high speed the shaft moves. An inertia force will let the knife on the tool shaft tends to disengage from the shaft, this could result in an impact between the tool shaft and the knife. Furthermore, sometimes, the knife could drop from the tool shaft because of the sudden stopping action. Also, the catching means could hit the knife if the knife is not securely engaged with the tool shaft under a condition of the sudden stopping action.
In order to improve the problem, manufacturers use a cam device to actuate the shaft, the cam device makes the tool shaft move along a smooth path so that the sudden stopping action mentioned above can be mitigated. Nevertheless, to achieve a precise curve moving path, a cam member of the cam device has to be manufactured precisely and a high price is incurred. Most of the medium or small size plants cannot afford the cam device so that a suitable device to rotate the tool shaft is needed.
The present invention intends to provide a device for controlling a tool shaft of a cutting machine, wherein the tool shaft is moved and controlled linearly and rotationally by the device so as to have a smooth moving path. By the operation of the device the problems of the conventional tool shaft are mitigated and/or obviated.